Abstract
The preparation and structural characterization of the very strong reducing agent W2(hpp)4, hpp = the anion of 1,3,4,6,7, 8-hexahydro-2H-pyrimido[1,2-a]pyrimidine, 1, has been accomplished. It has a short distance of 2.1617(4) Å for the quadruply-bonded W24+ unit. Compound 1 is very reactive and gives the triple bonded W2(hpp)4Cl2· 4CH2Cl2, 2 · 4CH2Cl2, upon crystallization after mere contact with the haloalkane CH2Cl2. The change in electronic configuration from the σ2π4δ2 in 1 to the σ2π4 system in 2 increases the W-W distance by ca. 0.09 to 2.2497(8) Å. W2(hpp)4 also reduces C60 and 7, 7′, 8, 8′-tetracyanoquinodimethide, TCNQ. The latter is reduced to the TCNQ2- anion while the W24+ unit is oxidized to the W26+ state.
| Original language | English |
|---|---|
| Pages (from-to) | 121-126 |
| Number of pages | 6 |
| Journal | Inorganic Chemistry Communications |
| Volume | 6 |
| Issue number | 2 |
| DOIs | |
| State | Published - Feb 1 2003 |
| Externally published | Yes |
Funding
We are grateful to the Robert A. Welch Foundation for financial support.
Keywords
- Ditungsten
- Guanidinate ligands
- Metal-metal bonds
- Strong reducing agent